EP-A 0 640 655 describes moulding compositions composed of aromatic polycarbonate, styrene-containing copolymers and graft polymers that can be rendered flame-resistant with monomeric and/or oligomeric organic phosphorus compounds.
EP-A 0 363 608 describes flame-resistant polymer blends composed of aromatic polycarbonate, styrene-containing copolymer or graft copolymer and oligomeric organic phosphates as flame retardants.
U.S. Pat. No. 5,061,745 describes polymer blends composed of aromatic polycarbonate, ABS graft polymer and/or styrene-containing copolymer and organic monophosphates as flame retardants.
A combination of organic phosphorus compounds and inorganic phosphorus/oxygen compounds or phosphorus/sulfur compounds is not described therein. Common to all the applications cited is that, to achieve an excellent flame-proofing with very short burning times, very large amounts of phosphates have to be used and these have an adverse effect on the stress cracking behaviour of the respective moulding compositions.
The demand for a property combination comprising outstanding flame resistance and very good stress cracking behaviour complies, in particular, with the demand for increasingly thinner moulded-part wall thicknesses.